Isolation of specific bone cell types by free-flow electrophoresis

The bone cells and fibroblasts from fetal rat calvaria can be isolated by collagenase digestion of the collagen matrix and separated into specific cell types by free-flow electrophoresis. The method involves injection of a specially prepared suspension of cells into a stream of buffer across which is maintained an electric field of 60 V/cm. The fetal bone cell types are differentially deflected toward the anode where they can be collected. Free-flow electrophoresis of this heterogenous cell preparation yields three distinguishable peaks which can be identified by morphologic, morphometric, and enzymatic characteristics. All three cell peaks have greater than 95% viability as judged by trypan blue exclusion and will grow to confluent monolayers in culture. The data indicate that these cell peaks may be comprised of osteoclasts and/or preosteoclasts, osteoblasts and/or preosteoblasts, and fibroblasts.